In the production of hydrocarbons from a plurality of underground formations penetrated by a single borehole, it is not unusual for this to be advantageously accomplished by the use of a plurality of well packers along the length of the wellbore to isolate certain formations or sections of formations from other formations or the rest of the wellbore. This procedure is often termed a stacked installation when speaking of the tools and packers used therein.
One method of establishing a stacked installation is to run a string of production tubing into the borehole with a packer located at the bottom and setting the packer at the lowermost position in the wellbore which has not yet received a packer. Using this method, each packer must be placed individually and each requires a separate trip of the work string for placement.
Alternatively, several packers may be run in a hole at the same time on a single work string or tubing string to be set simultaneously by hydraulic or mechanical means. Removal of the packers requires removal of all of the packers at one time with the work string or tubing string on which they were run in.
The present invention contemplates a method of running a plurality of packers into a borehole and selectively retrieving any portion of the number of packers, leaving those below the retrieved packers to remain in the borehole.